The present invention relates to a database and, more particularly, to a database system which appends attribute information to registered data, and performs registration, search, display, editing, printing, and the like based on the appended attribute information, its control method, and an information processing apparatus.
In general, a document database system which registers, searches, displays, edits, and prints document data by setting document attributes such as document names, keywords, and the like to document data is known. Also, a so-called distributed document database system including a plurality of kinds of document databases has been proposed.
In such distributed database system, if different document attributes can be set in units of document databases, attribute information can be conveniently set in correspondence with the types of documents.
However, in the distributed document database system which has attribute information inherent to databases, when a document is copied between document databases having different document attributes, document attribute data which is not present in the copy destination is deleted. For this reason, when document data may be copied between different document databases, all the document databases must have the same document attribute.
When all the document databases must have the same document attribute, document attributes unique to individual document databases cannot be set. For example, assuming an office including both a document database that registers patent publications and a document database that registers reports, it is convenient if the document database that registers patent publications can be searched by setting a publication number for a document as a document attribute. On the other hand, in the document database that registers reports, it is convenient if the database document can be searched by setting a document number for a document as a document attribute. However, when all the document databases must have the same document attribute, different document attributes cannot be set in units of document databases. For this reason, a document attribute which is not required in some document databases must be set for all the document databases, or only a common document attribute must be used. For example, document attributes “publication number” and “document number” need both be settable for the document databases for patent publications and reports.
When document attribute data which is not present in the copy destination is deleted, if a document is copied between document databases having different document attributes, data is automatically deleted. For example, assume that a document in a document database which sets “publication number” as a document attribute is copied to a document database which has no document attribute “publication number” but sets “document number”. In this case, even when the publication number of a source document is used in correspondence with the document number in the copy destination, the publication number data is deleted upon copying. For this reason, the operator must input a new document number by checking the document attribute of the source document. For this reason, operations become complicated, and another operator error may occur.
When the operator does not notice that a document attribute is deleted, he or she may experience a problem later. Especially, when a document is copied from a given document database and the source document is deleted, the document attribute of the source document cannot be checked, thus posing a serious problem.
Furthermore, when a document which sets a publication number is copied to a document database which cannot set publication numbers, and is copied again to the document database which can set publication numbers, the publication number set previously has already been deleted, and cannot be recovered. Hence, the operator must re-input the publication number, and still another operator error may occur.
In some cases, another document database is prepared, and is used as a backup for a plurality of other document databases. In such case, the backup database must have document attributes of all the document databases to be backed up. For this reason, when a document attribute that can be set in a document database is changed, that of the backup document database must also be changed, resulting in a heavy load on the operator.